Oyama, Yoichi 
  
Therefore, we made preliminary measurement using the analytical plotter in order to reduce the work load at the site. 
1). We inputted the peak coordinates of each surface which composes of the lower limit surface into the analytical 
plotter. 
2). We made an arrangement so that the judgment shall be made on real time as to whether the Z coordinate of a mess- 
mark is higher or lower than a point on a surface having the same X, Y coordinates. 
3). We made an arrangement so that an alarm is issued and the plotting operator is prompted for the attention when the 
value of Z coordinate of mess-mark is larger than the point of the surface. 
4). Then the plotting operator measured the topographies and ground objects which are close to or protruding over the 
surface within the plotting range. 
5). The plotting of ground objects was also made at the same time. 
2.2 Calculation by general purpose computer 
The difference of altitude between topographies and ground objects this acquired and the surface was calculated 
accurately by a general purpose computer. We outputted the results as a list (Table 1) and carried it at the time of actual 
measurement at the site. 
Table 1: Measurement values and calculation results 
  
  
Altitude Altitude ~~ Height of Altitude of 
NO  ofsurface ofground protruding protruding (B)-(A) X coordinates — Y coordinates 
(A) object — object (B) 
1 261.78 261.22 0.48 261.70 -0.08 -25570.500 -134374.063 
2 262.13 260.93 0.77 261.70 -0.43 -25556.055  -134400.141 
3 262.48 260.82 0.88 261.70 -0.78 -25541.016  -134424.914 
4 262.84 260.56 1.14 261.70 -1.14 -25526.359  -134450.945 
5 263.12 259.86 8.45 268.31 519 # -25495.006  -134459.878 
6 263.20 260.17 1.53 261.70 -1.50 -25511.355  -134477.070 
7 263.56 259.14 3.01 262.15 -1.41 -25496.395  -134503.211 
8 263.62 258.06 14.41 272.47 8.85 4 -25586.176  -134560.602 
9 26422 256.60 7.92 264.52 0.30 # -25513.082  -134575.516 
10 264.64 258.19 533 263.52 -1.12 -25451.680  -134581.445 
11 266.30 256.24 16.02 272.26 596 # -25297.063  -134651.531 
12 266.97 255.16 13.45 268.61 1.64 # -25396.098  -134773.336 
13 266.98 253.09 15.41 268.50 152 4 -25285.637  -134710.148 
14 267.45 251.30 21.42 272.72 52] 4 -25318.037  -134774.648 
15 267.73 250.30 16.71 267.01 -0.72 -25346.777  -134817.828 
16 268.08 246.48 19.79 266.27 -1.81 -25303.623  -134826.894 
17 268.79 249.23 14.94 264.17 -4.62 -25320.028 -134904.257 
18 268.86 248.68 20.69 269.37 -25337.232 — -134920.448 
  
  
  
# indicates those which is protruding over the surface 
2.3 Precise investigation by site measurement 
We actually measured the height of topographies and objects contained in the list and other objects which had been 
missed in the plotting works, and made investigation on the information of their name, owner, administrative unit, etc. 
We employed the measurement value of plotter for the height of trees, and acquired the actual height of structures from 
the design drawing if it was available. 
2.4 Construction of maps 
We calculated the height data accurately measured at the site as well as other information again by general purpose 
computer. The height was described on the maps for the topographies and objects protruding in a form of spot such 
buildings and high towers. Those which protruded on a form of space such as hills were expressed by placing hatching 
over them. In this study, we constructed plans at the scale of 1 / 10,000 and 1 / 20,000 as well as longitudinal section 
drawing which shows relative relation to the surface. These were developed by the ball point pen plotter. We traced 
them and plotted ground objects, and arranged it in a form of map. 
  
1098 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.